shift.im
Apply Vector Translation To Pixel Image
Applies a vector shift to a pixel image
Usage
## S3 method for class 'im':
shift(X, vec=c(0,0), ..., origin=NULL)
Arguments
- X
- Pixel image (object of class
"im"
). - vec
- Vector of length 2 representing a translation.
- ...
- Ignored
- origin
- Character string determining a location
that will be shifted to the origin. Options are
"centroid"
,"midpoint"
and"bottomleft"
. Partially matched.
Details
The spatial location of each pixel in the image
is translated by the vector vec
.
This is a method for the generic function shift
.
If origin
is given, then it should be one of the character
strings "centroid"
, "midpoint"
or "bottomleft"
.
The argument vec
will be ignored; instead the shift will be performed
so that the specified geometric location is shifted to the origin.
If origin="centroid"
then the centroid of the image window will be
shifted to the origin. If origin="midpoint"
then the centre of
the bounding rectangle of the image will be shifted to the origin.
If origin="bottomleft"
then the bottom left corner of the
bounding rectangle of the image will be shifted to the origin.
Value
- Another pixel image (of class
"im"
) representing the result of applying the vector shift.
See Also
Examples
# make up an image
X <- setcov(unit.square())
plot(X)
Y <- shift(X, c(10,10))
plot(Y)
# no discernible difference except coordinates are different
shift(X, origin="mid")